5 community and non-transient non-community water systems are listed for District of Columbia in EPA SDWIS. 3 were sampled under UCMR 5; 3 of those had at least one PFAS result at or above the reporting level, and 0 had a highest single result at or above a 2024 EPA limit (PFOA or PFOS 4 ppt, or Hazard Index 1).
District of Columbia map · Download: systems (CSV) · all results (CSV, gzip)
These are monitoring results collected under EPA's Fifth Unregulated Contaminant Monitoring Rule (UCMR 5) at entry points, where treated water enters the distribution system; they are not tap-water samples. They are not compliance determinations: compliance with EPA's 2024 PFAS limits is judged on running annual averages of compliance monitoring, required from 2029, so a single UCMR 5 result at or above a limit is not a violation. “< MRL” means the compound was not quantified at EPA's minimum reporting level; it does not mean zero.
Sampled under UCMR 5 (3)
| System | PWSID | City | Population | Highest PFOA (ppt) | Highest PFOS (ppt) | Highest HI | Highest single result |
|---|---|---|---|---|---|---|---|
| D.C. Water And Sewer Authority | DC0000002 | Washington | 632,323 | <MRL | <MRL | 0 | Other PFAS detected |
| Joint Base Anacostia - Bolling | DC0000004 | Washington | 20,411 | <MRL | <MRL | 0 | Other PFAS detected |
| Naval Station Washington - Wny | DC0000003 | Washington Navy Yard | 16,800 | <MRL | <MRL | 0 | Other PFAS detected |
Not tested under UCMR 5 (2)
UCMR 5 required monitoring by systems serving 3,300 or more people and by a representative sample of smaller systems. The systems below have no UCMR 5 results in EPA's data. Not tested is not the same as not detected: the absence of results says nothing about PFAS in their water.
| System | PWSID | Type | City | Population | Counties |
|---|---|---|---|---|---|
| Naval Observatory | DC0000005 | NTNCWS | Washington Navy Yard | 250 | District of Columbia |
| Washington Aqueduct Division. | DC0000001 | CWS | Washington | 0 | District of Columbia |